code: def to_json(self):
      data_json = {
          "new_columns": list(self._new_columns),
          "old_column": self._old_column,
          "min_datetime": str(self._min_datetime),
          "transforms": list(self._transforms),
      }
      return data_json
  
file_path: mljar-supervised/supervised/preprocessing/datetime_transformer.py
imports: import datetime
  import json
  import numpy
  import pandas
label_desc: Use image node_id 4 for calling the DateTimeTransformer obj's underlying member method code with example usage: obj.to_json() and returns: data_json